LEAK RESISTANT DESIGN - These vials are engineered with a leak-resistant design, offering reliability in preventing spills or leakage of contents. This feature is precious when storing liquids or sensitive materials. CLEAR TRANSPARENT GLASS - The vials are made from clear transparent glass, allowing for easy visibility of the contents inside. This transparency is essential for quickly identifying and accessing the materials stored within the vials. THREADED BLACK SCREW CAPS - Each vial comes with a threaded black plastic screw cap that securely seals the contents. The caps are easy to screw on and off, ensuring a tight and protective seal. 4ml capacity TJ86-GB250